# Classification-Then-Grounding: Reformulating Video Scene Graphs as Temporal Bipartite Graphs

arXiv: https://arxiv.org/abs/2112.04222 · HTML: https://mlsanity.com/paper/2112.04222/

## Key facts

- Cited by 23 papers in the map (data through 14 Oct 2026).
- Builds on 41 of its 59 references that are in the map.
- First posted on arXiv 8 Dec 2021.

## Builds on (most cited first, 30 of 41)

- [Attention Is All You Need](https://mlsanity.com/paper/1706.03762/) (2017)
- [Deep Residual Learning for Image Recognition](https://mlsanity.com/paper/1512.03385/) (2015)
- [Adam: A Method for Stochastic Optimization](https://mlsanity.com/paper/1412.6980/) (2014)
- [Microsoft COCO: Common Objects in Context](https://mlsanity.com/paper/1405.0312/) (2014)
- [Faster R-CNN: Towards Real-Time Object Detection with Region Proposal Networks](https://mlsanity.com/paper/1506.01497/) (2015)
- [ImageNet Large Scale Visual Recognition Challenge](https://mlsanity.com/paper/1409.0575/) (2014)
- [End-to-End Object Detection with Transformers](https://mlsanity.com/paper/2005.12872/) (2020)
- [Layer Normalization](https://mlsanity.com/paper/1607.06450/) (2016)
- [Quo Vadis, Action Recognition? A New Model and the Kinetics Dataset](https://mlsanity.com/paper/1705.07750/) (2017)
- [Simple Online and Realtime Tracking with a Deep Association Metric](https://mlsanity.com/paper/1703.07402/) (2017)
- [Localizing Moments in Video with Natural Language](https://mlsanity.com/paper/1708.01641/) (2017)
- [TALL: Temporal Activity Localization via Language Query](https://mlsanity.com/paper/1705.02101/) (2017)
- [Neural Motifs: Scene Graph Parsing with Global Context](https://mlsanity.com/paper/1711.06640/) (2017)
- [Auto-Encoding Scene Graphs for Image Captioning](https://mlsanity.com/paper/1812.02378/) (2018)
- [SCA-CNN: Spatial and Channel-wise Attention in Convolutional Networks for Image Captioning](https://mlsanity.com/paper/1611.05594/) (2016)
- [Counterfactual Samples Synthesizing for Robust Visual Question Answering](https://mlsanity.com/paper/2003.06576/) (2020)
- [QPIC: Query-Based Pairwise Human-Object Interaction Detection with Image-Wide Contextual Information](https://mlsanity.com/paper/2103.05399/) (2021)
- [MAN: Moment Alignment Network for Natural Language Moment Retrieval via Iterative Graph Adjustment](https://mlsanity.com/paper/1812.00087/) (2018)
- [CrossFormer: A Versatile Vision Transformer Hinging on Cross-scale Attention](https://mlsanity.com/paper/2108.00154/) (2021)
- [End-to-End Human Object Interaction Detection with HOI Transformer](https://mlsanity.com/paper/2103.04503/) (2021)
- [Multilevel Language and Vision Integration for Text-to-Clip Retrieval](https://mlsanity.com/paper/1804.05113/) (2018)
- [Memory Enhanced Global-Local Aggregation for Video Object Detection](https://mlsanity.com/paper/2003.12063/) (2020)
- [Spatial-Temporal Transformer for Dynamic Scene Graph Generation](https://mlsanity.com/paper/2107.12309/) (2021)
- [Reformulating HOI Detection as Adaptive Set Prediction](https://mlsanity.com/paper/2103.05983/) (2021)
- [Boundary Proposal Network for Two-Stage Natural Language Video Localization](https://mlsanity.com/paper/2103.08109/) (2021)
- [Deconfounded Video Moment Retrieval with Causal Intervention](https://mlsanity.com/paper/2106.01534/) (2021)
- [On Pursuit of Designing Multi-modal Transformer for Video Grounding](https://mlsanity.com/paper/2109.06085/) (2021)
- [Target Adaptive Context Aggregation for Video Scene Graph Generation](https://mlsanity.com/paper/2108.08121/) (2021)
- [Ref-NMS: Breaking Proposal Bottlenecks in Two-Stage Referring Expression Grounding](https://mlsanity.com/paper/2009.01449/) (2020)
- [Tree-Augmented Cross-Modal Encoding for Complex-Query Video Retrieval](https://mlsanity.com/paper/2007.02503/) (2020)

## Built on by (most cited first, 23 of 23)

- [The Devil is in the Labels: Noisy Label Correction for Robust Scene Graph Generation](https://mlsanity.com/paper/2206.03014/) (2022)
- [Compositional Prompt Tuning with Motion Cues for Open-vocabulary Video Relation Detection](https://mlsanity.com/paper/2302.00268/) (2023)
- [Integrating Object-aware and Interaction-aware Knowledge for Weakly Supervised Scene Graph Generation](https://mlsanity.com/paper/2208.01834/) (2022)
- [NICEST: Noisy Label Correction and Training for Robust Scene Graph Generation](https://mlsanity.com/paper/2207.13316/) (2022)
- [Pair then Relation: Pair-Net for Panoptic Scene Graph Generation](https://mlsanity.com/paper/2307.08699/) (2023)
- [Cross-Modality Time-Variant Relation Learning for Generating Dynamic Scene Graphs](https://mlsanity.com/paper/2305.08522/) (2023)
- [DIFFVSGG: Diffusion-Driven Online Video Scene Graph Generation](https://mlsanity.com/paper/2503.13957/) (2025)
- [Computer Vision for Primate Behavior Analysis in the Wild](https://mlsanity.com/paper/2401.16424/) (2024)
- [Rethinking the Evaluation of Unbiased Scene Graph Generation](https://mlsanity.com/paper/2208.01909/) (2022)
- [In Defense of Clip-based Video Relation Detection](https://mlsanity.com/paper/2307.08984/) (2023)
- [VrdONE: One-stage Video Visual Relation Detection](https://mlsanity.com/paper/2408.09408/) (2024)
- [Multi-Label Meta Weighting for Long-Tailed Dynamic Scene Graph Generation](https://mlsanity.com/paper/2306.10122/) (2023)
- [TRKT: Weakly Supervised Dynamic Scene Graph Generation with Temporal-enhanced Relation-aware Knowledge Transferring](https://mlsanity.com/paper/2508.04943/) (2025)
- [Synthetic Visual Genome 2: Extracting Large-scale Spatio-Temporal Scene Graphs from Videos](https://mlsanity.com/paper/2602.23543/) (2026)
- [MosaicThinker: On-Device Visual Spatial Reasoning for Embodied AI via Iterative Construction of Space Representation](https://mlsanity.com/paper/2602.07082/) (2026)
- [TD^2-Net: Toward Denoising and Debiasing for Dynamic Scene Graph Generation](https://mlsanity.com/paper/2401.12479/) (2024)
- [Video Relationship Detection Using Mixture of Experts](https://mlsanity.com/paper/2403.03994/) (2024)
- [Grounding is All You Need? Dual Temporal Grounding for Video Dialog](https://mlsanity.com/paper/2410.05767/) (2024)
- [Rethinking Multi-Modal Alignment in Video Question Answering from Feature and Sample Perspectives](https://mlsanity.com/paper/2204.11544/) (2022)
- [DiVR: incorporating context from diverse VR scenes for human trajectory prediction](https://mlsanity.com/paper/2411.08409/) (2024)
- [Language-guided Recursive Spatiotemporal Graph Modeling for Video Summarization](https://mlsanity.com/paper/2509.05604/) (2025)
- [Frequency-guided Multi-level Reasoning for Scene Graph Generation in Video](https://mlsanity.com/paper/2604.17298/) (2026)
- [Plug-and-Adapt: Multimodal Coreference Resolution at First Sight with a Pretrained Alignment Model](https://mlsanity.com/paper/2606.17950/) (2026)

## Abstract (arXiv)

Today's VidSGG models are all proposal-based methods, i.e., they first generate numerous paired subject-object snippets as proposals, and then conduct predicate classification for each proposal. In this paper, we argue that this prevalent proposal-based framework has three inherent drawbacks: 1) The ground-truth predicate labels for proposals are partially correct. 2) They break the high-order relations among different predicate instances of a same subject-object pair. 3) VidSGG performance is upper-bounded by the quality of the proposals. To this end, we propose a new classification-then-grounding framework for VidSGG, which can avoid all the three overlooked drawbacks. Meanwhile, under this framework, we reformulate the video scene graphs as temporal bipartite graphs, where the entities and predicates are two types of nodes with time slots, and the edges denote different semantic roles between these nodes. This formulation takes full advantage of our new framework. Accordingly, we further propose a novel BIpartite Graph based SGG model: BIG. It consists of a classification stage and a grounding stage, where the former aims to classify the categories of all the nodes and the edges, and the latter tries to localize the temporal location of each relation instance. Extensive ablations on two VidSGG datasets have attested to the effectiveness of our framework and BIG. Code is available at https://github.com/Dawn-LX/VidSGG-BIG.
